Conventionally, an ink jet recording apparatus that ejects ink onto a recording medium to form an image offers advantages of reduced noise, reduced running costs, compactness and good color imaging that make such an apparatus the device of choice in printers, copiers, facsimile machines and other, similar equipment.
Attempts to satisfy demands for higher-quality image output and faster recording speeds have led to increases in the number of ink-ejecting nozzles provided on the recording head and decreases in the recording cycles of the ink jet recording apparatus.
Further attempts to satisfy the above-mentioned demands involve increasing the resolution by increasing the image data transmission clock frequency (that is, shortening the transmission cycle).
The structure of the conventional ink jet recording apparatus is such that the clock signal is transmitted from the recording apparatus to the recording head, so the recording head, which scans the recording medium during recording, and the recording apparatus are connected to each other by a flexible cable or the like, with the clock signal, image data and so forth being sent to the recording head in the form of serial signals.
However, given the arrangement described above, the flexible cable that connects the recording head to the recording apparatus may be exposed to large electrical currents in the vicinity thereof that can generate noise in the transmission of signals via the flexible cable. Therefore, when transmitting high-frequency clock signals, the cable may sometimes act essentially as an antenna, generating noise, which in turn can cause devices in the vicinity of the recording apparatus to malfunction.
In addition, regulatory restrictions on the acceptable level of radiation emitted by electrical and electronic devices continue to become more stringent even as the speed with which the transfer of image data increases attendant upon increases in recording speeds.
Accordingly, it is critical to find ways to prevent ever-increasing levels of radiation generated inside devices such as ink jet recording apparatuses from leaking from such devices.